Ran a 12.3 @ 110 with a 1.73 60’ with my boost spiking to 24psi and tapering to 16 psi at redline because I had the soft spring in my MBC because the hard spring kept getting stuck. This was on pump gas, shifting to to 5th at 7k rpms instead of riding out 4th. (bad MR gearing). Probably could have gotten a 12.1 @ 112 if I’d ridden 4th out. I’m currently untuned for the Evo9 turbo. On the evo8 turbo I was tuned for 24 psi on pump with no knock by Jestr and he said it safe to run the same boost because all he’d have to tweak on my map is how well the boost holds up top. When the hard spring is in the car it will hold 21 psi at redline and it’s a night and day difference. I should have switched the springs out but I’d completely forgotten I had the soft spring in. I’d swapped them out the night before. Cant wait to get it retuned on the hard spring and go back

 

nice time... whats your mods?

 

AMS downpipe, AMS midpipe, AMS testpipe, AMS catback, Helix o2 housing, Maxford Exhaust manifold, Evo9 turbo, HKS RS intake, LPI upper and lower intercooler pipes, GRE front mount intercooler, GSC 272/272 intake and exhaust camshafts, ARP headstuds, Walbro 255 fuel pump, FORGE diverter valve (bov), FORGE Manual boost controller @ 24 psi, tapering to 21-22 psi at 7k, innovative wideband LC-1, Apexi turbo timer, TRE spec race transmission, stg2 ported head with titanium ferra valves, ACT stg1 clutch with ACT prolight flywheel.

 

nice run!

 

Not really that much better than your Dynoflash times with the stock VIII turbo, is it? This was with 3 more psi (24 vs 21) and on a IX turbo that makes about an extra 20whp over an 05 turbo, but you went from 12.41 to 12.30 with the same trap. I don't say this to get in an argument about Dynoflash vs Jestr. I say it as FURTHER indication that your car just isn't right for whatever reason. It's always been slower than it should be, and you have blamed a lot of it on Al in the past, but I think it's more the car than the tuner(s). This time, we can also confirm that it's also not a driver issue.

PS. When shifting to 5th on my 6spd, there was never a .2s/2mph difference for me at sea level - it was usually half a second slower or so. In fact, at this altitude, I was much quicker with higher traps when shifting to 5th due to the severe effect of altitude on the powerband.

 

i don't think you quite gave it a fair shot. with al's tune on the 05 turbo, i'd spike to 21 and hold 19 at redline. al's maps tend to have less boost and more timing. it's just his prefered method of tuning. with the 12.41 that i ran on al's tune, it was with me staying in 4th gear, and not wasting time shifting to 5th.

this run i ran the same time, with a drastic taper because of the soft spring. and wasted time shifting to 5th

if you need proof that it's just the spring that caused me to run slower, i can show you some street racing videos of my car with the hard spring

 

The soft vs hard spring has nothing to do with taper. That only has to do with the range of boost you can run. If you're already hitting your preferred boost level on the soft spring, then there is no downside to using it except that you can't go much higher if you want to use race gas.

It's also MUCH better to run less boost and more timing. Running higher boost just so that you have to detune the car is what causes high EGTs. It also generates more heat out of the turbo for no reason.

Street racing proves nothing, sorry.

 

Umm, read this thread I made about the two springs and affects on taper.

https://www.evolutionm.net/forums/sh...d.php?t=259636

ps. EVO has been chilling at the my shop for the last 5 weeks and is coming out this week, so I'll have MAP sensor logs of the hard spring having less taper then the soft spring soon.

 

I've used both springs and have logged both with no difference in taper. Of the thousands of others who have used both springs, this has not been a recurring phenomenon either. Likewise, my Hallman tapers the same as both springs in my Forge. On top of all that, I still have the stiff spring and taper 10psi due to altitude - it has nothing to do with which spring I use. The only difference is the max boost I can create.

 

in any normal situation i'd trust your judgement clay. however i've seen with my own eyes the difference of what my soft and hard spring do to my taper. its a night and day difference. next time i go to the track, ill be happy to prove it

 

DUDE, good times - I mean, for a n00b like u, pwn! we gotta catch up soon. . .